Fig. 3. Tenascin-W is first expressed in maxillary processes of mouse embryos. Immunohistochemistry of tenascin-W (A), tenascin-C (B) and a merged picture (C) in a section through an E11.5 mouse embryo reveals co-expression in the maxillary process (mp). Tenascin-W is still expressed in the mp at E14.5 (D). In situ hybridization analysis of E12.5 mouse embryos with probes against tenascin-W reveals expression in `moustache-like' structures corresponding to the mp when viewed from below (arrows, E) and in whole embryos (arrow, F). Embryos incubated with sense control probes were unlabeled (not shown). Scale bars, 100 µm (A-D), 1 mm (E,F).